Selenium

**Definition:** An element with the atomic symbol Se, atomic number 34, and atomic weight 78.97. It is an essential micronutrient for mammals and other animals but is toxic in large amounts. Selenium protects intracellular structures against oxidative damage. It is an essential component of GLUTATHIONE PEROXIDASE.

**Tree numbers:** - D01.268.185.850 - D01.578.700

**Synonyms:** - Selenium-80